The need

Dengue fever – a growing global threat

Dengue fever is the world’s fastest growing mosquito-borne disease. Over 50 million people suffer from dengue fever each year, and 40% of the world’s population may be at risk. It is quickly becoming even more widespread, and is growing in severity.

Dengue symptoms range from mild and flu-like to high fever, rash, severe headache, pain behind the eyes, muscle and joint pain. The joint pain can be so severe that dengue has been given the name ‘breakbone fever’. Nausea, vomiting, and loss of appetite are also common. In the more severe form, sometimes called dengue haemorrhagic fever (DHF), blood vessels start to leak and cause bleeding from the nose, mouth, and gums. Without prompt treatment, the blood vessels can collapse, causing shock (dengue shock syndrome) and ultimately fatality.

Around 25,000 people die from Dengue Fever each year. Severe cases require hospitalization and constant monitoring. Dengue is also an extremely expensive disease, estimated to cost the global economy over US$5 billion per year.

Dengue fever occurs in most tropical areas of the world. It is common in Asia, the Pacific, Australia, Latin America and the Caribbean and is continuing to spread having now reached North America. A recent Natural Defence Resource Council report shows that 28 US states are now at risk.

Current control methods aren’t working

There is neither specific medication nor vaccine for dengue. The only way currently to control the disease is to control the mosquito which spreads it: the dengue mosquito, Aedes aegypti.

Existing methods of controlling the dengue mosquito, which include spraying or fogging using chemical pesticides, have failed to stop the spread of the disease. That’s partly because the mosquitoes have developed resistance, but also because the Aedes aegypti mosquito lives in and around human habitation – even breeding happily in vases, water jars and other vessels in people’s houses – so it can be very difficult to reach.